Thread-measuring mechanism for sewing-machines.



C. PEDERSEN. THREAD MEASURING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED DEO.10, 1907 mvzmev G Hanan Pedman Patented Sept. 15, 1908 Witnesses UNrrnDsTArEs PATENT orrrcn CHRISTIAN PEDERSEN, or's'r. LoU1s,MI-ssoURi,- issrcnon'ro LANDIS MACHINE COMPANY,

or ST. LOUIS, MISSOURI, A CORPORATION or MISSOURI.

Specificationof Letters Patent.

Patented Sept. s, 1908.

- Application filed December 10, 1907. Serial No. 405,926.

To all whom it may co'rwern:

Be it known that I, CHRISTIAN PEnnRsnN,

- a citizen of the lnited States, residing at St.

Louis, Missouri, have invented a certain new and useful Improvement in 'lhread-MeasuringMechanis'm for Sewing-Marcilines, of which the following is a full, clear, and exact de scriptiomslu-h as will enable others skilled in the ari to which it appertains to make and use the same, reference being had to the acmnnpunying drawings, forming part of'this specification, in which Figure 1 is a side elevation partly in section, of a sewing machine provided with a thrmidmieasuring mechanism embodying the features of my invention; Fig. 2 is a detail fronteleval ional view of the take-up arm andits actuating mechanism and also the stop cam which limits the upward movement of said arm; Fig. 3 view of the clamping plates between which theneedle thread passes; and Fig. 4 is a detail perspective view of the stop cam whichlimits the movement ofthe take-uparm.

This invention relates to sewing machines, and particularly to the thread-measuring mechanisms on wax-thread sewing machines such as are used for sewing leather.

The main object of my invention is to provide a tmead-measuring mechanism of simple construction in which the movement of the shuttle is utilized to draw the needle thread from the supply spool, the quantity or amount of thread that is drawn off at each cycle of operations being controlled or govcrned by the'thickness ofthe stock being operated on.

Referring to the drawings which illust ate the preferred form of my invention, 1 d signates a circularly moving shuttle and 2des1gnates a curved needle arranged above the work-table 3 and adapted to pass downwardly through the stock being operated on to receive the needle thread whichv it pulls upwardly through the stock to form a loop for the shuttle to pass through so as to' lock the needle aml shuttle threads together. The

mane thread 4 which leads from a supply spool, not shown, passes over idlers 5 and 5 to a roll on the front end of a take-up arm 6 arranged below the work-table, said take-up.

arm being loosely mounted on a shaft 7 journaled in a bearing 8. The shaft 7 1S rocked by means of a cam-actuated lever 0 that is is an enlarged perspective said shaft. is provided with a second arm 11 7 having a portion that is arranged in alinement with the take-up arm 6 so as to depressit to set the stitch when the shaft 7 is rocked in one direction. The needle thread 4-passes between a pair of plates .12 and 13, and means is provided for forcing these plates together to lock the thread and prevent it from being drawn oil the supply spool. The "means herein shown for actuating the clamping plates consists of an elbow-shaped lever 14 rovided on its vertically disposed arm wit 1 a roller 15 that travels on the periphery of the cam block 16 which actuates the lever 9, and on the horizontally disposed arm of said elbow lever 15 is an adjustable device 17,.that bears upon the top clamping plate 13. The

clamping plate 13 is preferably formed of spring material,' and is connected at one end i by means of fastening devices 13- t0 the underneath rigid clamping plate 12.

The periphery-of the cam block 16 has a cut-out portion 16* and when the roll on the vertical arm of the elbow lever 14 is traveling in said cut-out portion the device 17 in the horizontal arm of said lever will not exert sufficient pressure on the plate 13 to lock or clamp the needle thread.

The presser-loot consists of a pi'votall mounted lever 18, the inner end of whic bears upon the stock A and clamps it down upon the work-table and the rear end of said 'lever is connected to a link 19 that is fastened to an arm 20 on a rock shaft 21 rovided with a cam' 22 that is arranged in alinement with the take-up arm 6 so as to control and limit its upward movement. As this stop cam 22 is moved by the 'presserfoot 18 it is obvious that the positionof said cam will vary according to the-thickness of the stock, and as said cam limits the upward movement of the take-up arm, the time at ,which said take-up arm comes to rest in its upward movement will vary.

During the time the needle is moving upwardly through the stock to form alooo in the needle thread 4, said thread will be locked or clamped by the plate 13 so that no thread can be drawn oil the supply spool, the

slack in the thread between the clamping plates. and the stock being taken up by the take-up arm 6. After a loop has been formed in the needle thread and the point of the in other types of sewing 1 shuttle has passed through said loop the cutout ortion 16 in the periphery o the cam bloc 16 comes into ahnement with the roll on the vertical arm of the elbow lever 14,

thus permitting said lever to move slightly of the needle and also the movement of the shuttle when it first enters the loop in the thread pulls the take-up arm 6 upwardly and while said take-up arm is moving upwardly no thread willbe drawn from the sup ply spool. As soon asthe take-up arm comes into engagement with the stop cam 22, how ever, al the slack in the thread will have been taken up and the movement of the shuttle will pull a quantity of thread from the supply spool.

The amount of thread that is drawn off the supply spool at each cycle of operations will vary according to the thick-' ness of the stock, due to the fact that the time at which the take-up arm comes to rest in its upward movement varies according to the position of the stop camwhich is controlled by the presser-fo ot. When very thick stock 1s being operated on the upward movement of the take-up arm is arrested'soon after the pointof the shuttle has entered the loop in the thread so that the shuttle will draw more thread from the supply spool than when thin stock is being operated on because the takeup arm is not arrested as soon in its upward movement when thin stock is being operated on as when thickstock is bein operated on. With thin stock the shuttle oes not commence to draw the threadfrom the su ply spool until some time after it has entered the loop in the thread so that only a small quantity of thread will be drawn oif the supply s 001. After the shuttle has passed out of t e loop in the thread the take-up arm 6 is moved downwardly to draw the threads into the stock and set the stitch. While Ihave herein shown my invention applied to a sewing machine having a curved needle arran ed above the work it will, of course, be un erstood that my broad idea could be embodied machines.

I prefer to make the nk l9 adjustable so that the length of same can be varied to cause the stop cam 22 to o erate at the pro er time, and to this end I lave rovided sai link intermediate its ends wit a turn buckle 19. The sto cam 22 is also made adjustable for a simi ar purpose, said cam consisting of a plate that is adjustably conn}ected by means of screws to the hub 22 of t 1e cam.

tially as described.

scarce Having thusdescribed my invention, what I claim as new and desire to secure by Letters Patent s? 1. A sewing;- machlne provided with a thread-measuring mechanism, comprising a shuttle which is adapted. to enter a loop in the needle thread, a device for taking up the v the will draw thread from the supply; sub

stantially' as described. a

2. A sewing machine provided with a thread-measuring mechanism, compnsing shuttle which is adapted to enter a loop in the needle thread, a device for taking up slack in the thread between the source or sup ly and the stock being operated on, a memer for arresting the movement of the takeup device before the shuttle has passed out of the loop in the thread to cause the shuttle to draw thread from the supply, a resser-foot,

and aconnection between said member and presser-foot; substantially as described;

3. A sewing machine provided with a 4 thread-measuring mechanism which consists of the following elements, a shuttle that is adapted to enter a loop inithe needle thread, automatic means for intermittently clamping and releasing the needle thread, a take-up device engaging. the thread between the stock hein operated on and said clamping means, and means controlled by the presserfoot of the machine for arresting the movement of said takedevice before the shuttle has assed out of the loop in the thread so that said shuttle Will 1111 different quantities of thread 03 the supp y as the stock varies in thickness; substantially as described.

4. A sewing machine provided with a thrad-measuruig mechanism, comprising a shuttle that is adapted to pull thread from the supply, a take-up arm, a cam adapted to engage and limit the upward movement of said arm, a resser-foot, and aconnection between said cam and resser-foot; substan- 5. A sewing machine provided with a presser-foot, a take-up arm for keeping the needle thread taut, a cam for limiting the movement of said take-up arm in one direction, a.presser-f'oot, a connection eetween said cam and resser'foot, and a shuttle for pulling threa from the supply after said take-up arm has come to rest; substantially as described.

6. A sewing machine provided with a Presser-foot lever, a take-up arm for keeping the needle thread taut, a shaft provided with a cam that is arranged in alinement with the take-up arm for limiting its movement in one direction, a connection between said shaft seems and the rear end of the resser-foot lever, and a shuttle adapted to pull a quantity of thread from the supply after the take-up arm has engaged said cam; subsuantiallyas described.

7. A sewing machine provided with a loosely mounted take-up arm for keeping the needle thread taut, an adjustable stop cam for limiting the movement of said take-up in arm in one direction, a pivotally mounted presser-foot, a connection between said resser-foot and stop cam, and a shuttle adapted to pull thread from the supply after the stop cam has arrested the movement of the take-up arm; substantially as described. 8. A sewing machine provided with a clamping plate under which the needle thread passes, means for causing said plate to inter mitten tly lock and release the needle thread,

as a take-up arm for keeping the thread taut, a

cam for limiting the 'movement of said takeup arm in one direction, means controlled by the thickness of the stock being 0 erated on for determinin the position of sai cam, and

a shuttle for drawing thread oil the su ply after the take-up arm has been arrests by said cam; substantially as described.

9. A sewing machme provided with a yielding plate underneath which the needle thread passes, a lever adapted to engage said plate, a cam for intermittently actuating said lever to cause said plate to lock said thread, a take-up arm for keeping the thread taut, a device actuated by the presser-foot of the machine for limiting the movement of said take-up arm intone direction, and a shuttle adapted to draw thread from the supply after the take-up arm has been arrested by said device; substantially as described.

10. A sewing machine rovided with a tension device throughwhic the needle thread passes, a take-up device for keeping the thread taut between saidtension device and the stock being 0 erated on, a needle for forming a loop in t e thread, means for locking the thread, a shuttle adapted to enter the loop in the thread, a resser-foot, and means controlled by the resser-foot for arresting the movement of tie take-up device before the shuttle has passed out of the loop in the thread so that said shuttle will draw a quantity of thread of) the supply; substantially as described.

In testimon whereof I hereunto affix my signature in tr e presence of two Witnesses, this seventh day of December 1907.

CHRISTIAN PEDERSEN.

Witnesses:

WELLS L. CHURCH, GEORGE BAKEWELL. 

